1. Field of the Invention
This invention relates to an adapter plate for an electrical connection, and more particularly, a multi-function electrical connection between a battery charger or the like and a battery pack having a plurality of interacting electrical contact pins.
2. Description of Prior Art
In U.S. Pat. No. 4,218,107, assigned to the same assignee as the present invention, a battery pack connection was disclosed which includes a female plate that is secured, for example, directly to a portable device such as a battery charger. The female plate is formed with a plurality of keyholes together with at least one male terminal with the keyholes and the terminal extending in the same direction but with the terminal being positioned within a recess spaced beneath the plane of the female plate. A male plate cooperates with the female plate and may form one side of a battery containing receptacle or pact. The male plate has a plurality of circular headed projections extending therefrom and at least one female terminal positioned within a housing that projects from the plane of the male plate.
In use, the female plate is fixed and connected to the electrical charger device and if the male plate is part of the battery pack, the user positions the male plate against the female plate with initial alignment occurring between the recess and the housing and with said alignment preventing lateral shifting of the plate with respect to the slots of the keyholes. The use can then only move the male plate in the direction of the keyhole slots until the headed projections enter into circular openings of the keyholes. The male plate is then further moved to position the projections within the slots of the keyholes with said movement causing electrical connection between the male and female terminals, so that the battery pack carried by the male plate may be recharged.
When the male plate has achieved its connected position, a tensioned flexible strip that is positioned behind one keyhole reverts to its normally biased position wherein it has a ledge which engages the head of the projection in said keyhole and prevents the two plates from moving from their connected position.
For removing the plate, the user merely bends the flexible strip from its normal position which unlocks the engagement between the strip and the projection to thereby permit the male plate to be moved so as to position the headed projections within the circular openings of the keyholes. At this position, the terminals have been disconnected and the male plate can be removed from the female plate.
In an improved battery pack connection disclosed in U.S. patent application Ser. No. 068,350, filed Jul. 1, 1987, now U.S. Pat. No. 4,810,204 entitled Battery Pack Connection, assigned to the same assignee as the present invention, the flexible locking strip is replaced by a positive, thumb-actuated pivoted locking mechanism having a locking pin adapted to be positioned over one of the threaded projections on the male plate after it is seated in the slot portion of a corresponding keyhole slot in the female plate. Upon pivoting of the mechanism with one hand, the pin can be removed from the path of movement of the head in the keyhole slot against the bias of a spring which provides a tactile feel upon opening and pivoting of the locking mechanism immediately conveying the position of the locking mechanism to the user that there is an unobstructed path of movement or clear keyhole slot. With the other hand, the entire male plate and headed projections can be moved up and out of corresponding closed keyhole slots, breaking the electrical connection between the terminal contacts on the male and female plates, and permitting the male plate and its batteries to be replaced by another pack or interchanged with another male plate containing a battery pack to be recharged, by reversing the procedure and repivoting and seating the locking pin over one of the headed projections. This is accomplished by simply releasing the locking mechanism, which is repositioned upon release by the return force of the leaf spring.
Additionally, instead of molding the female and male plates completely in one piece including support structure for the female and male contact terminals, respectively, on each plate, the terminals are provided on removable and adjustable terminal blocks for ease of assembly with wire connections exterior of the plates.
The female terminal block is adapted to be slid into the male plate with a U-shaped opening surrounding a stationary post. The upper and lower edges of the block are confined between upper and lower support shoulders forming a groove, which allows the connector block a specified amount of movement in all directions on a horizontal plane. This arrangement also permits preassembly of the contacts in the block and their attachment to wire connections with the battery associated with the male plate, exterior to the male plate, and once the block is slid into place on the male plate and the plate connected in turn to the female plate, the female contact terminals accepting the male contact terminals will self-align and make appropriate contact. This removes the necessity of precisely molding the contact placements in both the male and female plates.
Similarly, the male terminal block in the female plate can be separated from the female plate and slid onto the plate from the rear, riding over a cantilevered spring finger which snaps back positioning a shoulder behind the bottom edge of the block to hold it in place. Shoulders on the interior of the female plate limit inward sliding movement of the block. Male terminal contact pins can then be used to threadedly secure and lock the block against movement to the interior of the plate. As with the female connector block, the removability of the block allows assembly of electrical wiring from the device power is to be supplied to, exteriorly of the female plate. This invention relates to this electrical connection between the male and female terminal blocks, their pin mountings, the pin functions, and the manner in which the pins are activated.
In U.S. Pat. No. 4,822,296, also assigned to the same assignee as the present invention, the electrical connection includes an electrical connector block provide on a female plate secured to an electrical device, such as a battery charger, although the female plate can be connected to a device, e.g., a camera or other portable device, which can be used to obtain and discharge power from a battery, rather than a device to charge a battery. A battery pack mounted on a male plate is releasably locked to the female plate and has electrical contacts in electrical communication with the battery pack to, for example, remove a charge from the battery charger to the battery pack or to establish a power connection to drive an electrical device, For purposes of discussions to follow, it will be assumed that the female plate is mounted on a battery charger, unless otherwise indicated, to recharge a battery pack carried on a male plate.
Upon locking the male plate to the female plate, the electrical contacts on the male plate are brought into electrical engagement with a plurality of contact pins on the electrical connector block mounted on the female plate. The outermost pins on the electrical connector block are expandable banana plugs providing a positive (+) and a negative (-) circuit connection to allow powering of a device by a battery/power supply or recharging of a battery carried by the male plate and are received in cylindrical tubular contact elements on the male plate. The remaining pins on the female connector block all comprise a piston adapted to move linearly within a cylinder against the bias of a coil spring. The piston head may be enlarged for contact with a correspondingly located tubular pin or terminal carried by the male plate or may have a reduced diameter portion to conserve space, which extends upwardly to effect the requisite contact with a solid contact pin.
Upon depression of the piston against the bias of the coil spring within its cylinder by one of the contact pins on the male plate, an electrical circuit can be established through the piston in sliding engagement with its cylinder. Each cylinder can be electrically connected to one or more charger circuits, which circuit can be used to energize a display, e.g., of a gauge to visually record the remaining voltage in the battery pack as it is charged or before recharging, if necessary. Another pin can be used to energize a circuit to enable a temperature responsive cut-off circuit in the charger to be activated so that the charger will not overheat when in use. Another one of the remaining contacts may, e.g., be used to establish an electrical circuit directly from the battery pack being recharged through its cylinder to sense whether the battery is resistor encoded or of a certain type compatible with the charger. The remaining pin can be used for a similar, albeit different communication between the battery pack and charger, e.g., to provide an analog output indicative of the remaining capacity in the battery, prior to recharging. The springs within each cylinder, upon depression, assure the maintenance of electrical contact between each piston and its corresponding contact pin on the male plate and allow depression of a contact on the female plate even in the absence of a corresponding pin on the male plate to establish a circuit at that location, so the female plate and its electrical connectors are compatible with a male plate provided with less circuits and function capability.